Dual subs time aligned and eq'd
One sub is about 7 feet away from your corner, the other 14 feet.
At some frequency the direct waves will be out of phase... cancellation.
80 Hz has a 14 foot wavelength, half of that is seven feet, so, looks like they cancel around that frequency to me.
(the above does not take the effect of the rest of the room into account)
Experiment with the timing?
I have a hole around 48Hz at the listening position, even with symmetrical speaker position, because the back of the room is open on one side,.
I can get rid of it by notching the output of one channel and boosting the other.
However, I don't sit in a corner, and haven't contemplated that arrangement.
Going to try that now. Thanks. As soon as I posted and looked at my setup again I was thinking about those subs not being equidistant. Even if I got cancelations but closer to 100hz or so, I would be happier since that's where I cross to mains.Izzit possible to move the sub pictured at the bottom farther along the same wall? Perhaps near the window?
What sort of bass response can you generate, with a single sub.
It may very well be that you have room mode issues at the listening position, resulting in cancellation at those particular frequencies. There are other calculators, but if you use this simple one and enter correct room dimensions you can easily get the picture. Even though you should take the calculations with the grain of salt, AFAIK, any corner of any room is rarely a good listening position because many of the modes accumulate there. The Bolt area that this and other calculators suggest for a good listening position almost never includes any of the corners. I hope this helps.
not really possible unfortunately I've tried 80 and 90. Problem is mains have the same null so my only option was to get the subs to play through 80-90hz. Almos like having two drivers that don't extend all the way to the XO which means there's nothing you can really do except use different drivers or add a filler driver.Pull the seating out of the corner, try putting the subs behind it. Also, what is your crossover point? Worth measuring 60, 80, and 100.
XO has to be 80-90hz because mains have the same dip in the room at 80-90hz.What crossover region are you using for subs/main speaker?
How about just try one sub and try with differwnt phase of the sub? I recently used REW to match my sub to my speakers in my computer room setup and phase of 0 vs 180 makes a difference.Thank you. I think this is the hard truth. Both the mains and subs have nulls there and I've tried moving the subs basically everywhere against the wall.
not really possible unfortunately I've tried 80 and 90. Problem is mains have the same null so my only option was to get the subs to play through 80-90hz. Almos like having two drivers that don't extend all the way to the XO which means there's nothing you can really do except use different drivers or add a filler driver.
XO has to be 80-90hz because mains have the same dip in the room at 80-90hz.
I see that both subs by themselves looks OK. It is when you add in the speakers you have issue.Ok, this is a mains problem not a sub problem. The real dip is at 100hz or 90-130hz. Yikes. I tried moving the standmounts to the floor to see if having the woofer nearer to the floor would fill that gap and it definitely helped. So perhaps towers with bass drivers closer to the floor would solve this issue. View attachment 125467View attachment 125465View attachment 125464View attachment 125463View attachment 125466
This is interesting. I might give this a shot. I think I accidentally set my XO to 80 when it needed to be 90hz for the mains plus sub sweep which made the gap larger. The lowest dip there is at 100hz which I don't want the subs to play anyway or I'll be able to localize them during playback especially all the way up to 140hz where the gap ends. I also forgot to adjust the alignment with mains since I adjusted the alignment between subs.I see that both subs by themselves looks OK. It is when you add in the speakers you have issue.
You may have to totally give up eq both subs together independent of matching to mains.
Have you tried independently matching right sub to right speaker and left sub to left speaker?
I did that with REW when I was using twin subs and I was really surprised that I needed to use totally opposite phase setting for my subs. Still sounded great.